The Metabolic Atlas portion of the Tissue Atlas enables exploration of protein function and tissue-specific gene expression in the context of the human metabolic network. For proteins involved in metabolism, a metabolic summary is provided that describes the metabolic subsystems/pathways, cellular compartments, and number of reactions associated with the protein. Over 120 manually curated metabolic pathway maps facilitate the visualization of each protein's participation in different metabolic processes. Each pathway map is accompanied by a heatmap detailing the mRNA levels across 37 different tissue types for all proteins involved in the metabolic pathway.